Maldonado, associate professor of psychiatry and medicine at Stanford and chief of the medical and forensic psychiatry section at the Stanford University Medical Center, offered clinical guidance at the recent US Psychiatric and Mental Health Congress in San Diego.

While Maldonado explained that each entity has distinctive characteristics, there are several general clues that aid in identifying “organic” mental disorders (Table). In addition, Maldonado said, several prescription drugs (eg, corticosteroids, opioids, cancer chemotherapies, antiparkinsonian medications), substances of abuse (eg, cocaine, alcohol, phencyclidine [PCP]), and toxins (eg, heavy metals, paint, organophosphate insecticides) are linked with anxiety, mood disorders, and psychosis. Be suspicious if the patient is taking prescription drugs that have psychoactive effects, has a history of substance abuse, may have been exposed to toxins, or is taking multiple medications, he said.

“I happen to be the psychiatrist for the transplant teams at Stanford, and we have found that some transplant patients take over 20 different kinds of supplements that are not part of their therapy,” he said. “The other day, I . . . asked a patient to show me a list of his medications. He pulled out a bag of prescribed medications. I asked him if he took anything over-the-counter, and he brought out a bigger bag.”

Maldonado discussed more than 27 medical and neurological disorders that present with psychiatric symptoms, offered “pearls” for timely diagnosis, and discussed potential management and treatment strategies, some of which are described here.

Endocrine disordersHypothyroidism (myxedema madness) associated with rapid onset may clinically present with delirium and psychosis, according to Maldonado. Myxedema madness refers to the cognitive and psychotic symptoms, such as paranoid delusions, seen before the availability of effective treatment. In older adults, he added, hypothyroidism may present with dementia-like symptoms.

Subclinical hypothyroidism can be virtually indistinguishable from depression and is often characterized by depression, memory loss, cognitive impairment, and fatigue.

Hyperthyroidism (Graves disease) can present with anxiety, shortness of breath, sleep problems, and emotional lability. The disorder may be misdiagnosed as a mood or anxiety disorder, said Maldonado. Clinicians also have to think about CNS intoxication and consider whether the patient is using illicit drugs, such as cocaine.

In patients 65 years and older, hyperthyroidism can present with psychomotor retardation and cognitive deficits, often leading to a misdiagnosis of depression (known as apathetic hyperthyroidism). In patients with bipolar disorder, hyperthyroidism can lead to mania, he warned.

Pheochromocytoma, a catechol­amine-secreting tumor, can present with a number of symptoms. Primarily it mimics panic anxiety symptoms, including “paroxysmal attacks of anxiety,” according to Maldonado.

“These patients have many of the classic symptoms of anxiety disorder. But if you take a very good history, you will find that the anxiety attacks caused by pheochromocytoma do not meet the diagnostic criteria for panic attacks,” he said. “The diagnosis is not that difficult, although clinicians must have a high level of suspicion. Diagnostic tests include 24-hour urinary catecholamines and metanephrines; CT or T2- weighted MRI of the head, neck, and chest; or clonidine-suppression test. You can also massage the adrenal glands, which will produce a surge of catecholamines, and the patient will experience symptoms of a panic attack.”

The treatment of choice is to remove the tumor. But Maldonado cautioned that all the patients should be treated with b-blockers before surgery to prevent intraoperative hypertension.